In general, an automotive air conditioning device comprises an intake unit for introducing outside and inside air, a cooler unit for cooling the introduced air and a heat for heating the introduced air, these three units being combined in series and installed in a limited space of a vehicle cabin, such as a space defined below an instrument panel.
However, due to the in-line connection of the three units, the automotive air conditioning device is compelled to have an enlarged size. Thus, when such device is mounted in a small car, the smaller vehicle cabin space is further limited, which is undesirable.
In view of the above, as is shown in FIG. 18, there has been proposed a device in which a cooler unit 1 and a heater unit 2 are positioned close to each other and aligned along a fore-and-aft direction of the vehicle thereby to reduce not only a longitudinal size "L" of the vehicle but also a lateral size of the same. Furthermore, in this device, for reduction of size, the distance between an evaporator 3 and a heater core 4 is reduced and a mix door (which will be referred to as just "door" hereinafter) 5 for producing cooler and/or warmer air is reduced in size.
As is known, the evaporator 3 is a device through which a low temperature low pressure~refrigerant, which flows in a refrigerating cycle, flows for producing a cooled air by conducting a heat exchange between the refrigerant and an induced air. While, the heater core 4 is a device through which a highly heated engine cooling water flows for producing a heated air by conducting a heat exchange between the cooling water and an induced air.
Denoted by numeral 6 in the drawing is a defroster door which, in a defrosting mode, opens a defroster opening 6a for defrosting a window, denoted by numeral 7 is a ventilation door which, in a ventilation mode, opens a ventilation opening 7a for blowing a cooled air against an upper part of a passenger, and denoted by numeral 8 is a foot door which, in a foot mode, opens a foot opening 8a for blowing a warmed air toward the upper part of the passenger.
However, in the unit having the above-mentioned construction, the reduction in size of the door 5 tends to cause a difficulty with which distribution of cooled air and warmed air is controlled. Thus, in some devices, as is illustrated by a broken line in the drawing, an auxiliary door 5a is provided for controlling the amount of air led to the heater core 4. However, in this case, the addition of such auxiliary door causes a complicated and highly costing construction, which is of course undesirable.
Accordingly, recently, there has been proposed, as is shown in FIG. 19, a much compact automotive air conditioning device (see Japanese Utility Model Provisional Publication 6-71222).
In the device, for achieving the compact construction, a cooler unit 1 and a heater unit 2 are integrated, and an evaporator 3 and a heater core 4 are positioned close to each other. That is, since the mix door 5 pivoting about a rotation axis 5b needs a relatively larger mounting space, a flat plate door 9 (the door shown in the drawing comprises two doors 9a and 9b which are connected through pins pa and pb to a door actuating mechanism comprised of a link mechanism) is employed, the flat plate door being slid up-and-down along a rail 9c for effecting the temperature control.
However, a door mechanism possessed by the above-mentioned vertically sliding type tends to show weak points in operability and sealing performance. That is, in order to prevent air leakage around the door 9, it is needed to remove or minimize a clearance between the rail 9c and the door 9. However, if the clearance is too small, the sliding resistance become increased causing non-smoothed movement of the door 9. This undesired phenomenon equally occurs even if a sealing member is arranged between the door 9 and the rail 9c. While, if, for achieving a smoothed movement of the door, a larger clearance is provided between them, the undesired air leakage tends to occur. That is, in this case, antinomic matters take place.
In a door mechanism of a slide door type wherein, like the door 9 described in the above-mentioned publication, a plate type door is slid, it is difficult to achieve a satisfied sealing. That is, although a sealing needed when a linearly running door comes to a terminal position is adequately achieved by only putting a seal member between the door and a member to which the door contacts, permanent deformation of the seal member takes place instantly because the flat seal member is pressed each time the door is actuated. In view of this, it is difficult to keep an adequate sealing for a long time. That is, even when the door comes to the terminal position that is, close position, undesired air leakage tends to occur in relatively early time, and thus, if such slide type door is used as the mix door, the temperature control performance is inevitably lowered due to the poor sealing.
While in a case wherein, like the above-mentioned door 9, the sliding mechanism is composed of a link mechanism, the connection between the pin and the link tends to produce a play upon operation of the door. When the door is applied with a certain pressure, noises caused by the play tend to be produced which are transmitted to the vehicle cabin to make passengers uncomfortable.
The present invention is provided for eliminating the above-mentioned drawbacks possessed by the conventional techniques. That is, a first object of the invention is to provide an excellent door mechanism of an automotive air conditioning device, which is compact in size, smoothly operable, superior in sealing performance and temperature control performance and suppressed from producing noises.
Furthermore, in the automotive air conditioning devices of these days, there has been developed a type which has a so-called fresh-ventilation mode and can blow a cooled air into the vehicle cabin from a ventilation opening when needed.
The automotive air conditioning device of this type comprises, as is shown in FIG. 20, a conventionally constructed automotive air conditioning device which includes an outside air intake opening 161, an inside air intake opening 162, an intake unit 160 having a fan F and a motor 164 installed therein, a cooler unit 101 having an evaporator 103 (viz., part constituting part of a refrigerating cycle) installed therein and a heater unit 102 including a heater core 104 through which engine cooling water flows, a mix door D, a bypass passage B, a warmed air passage H and a mix chamber E, and further comprises a cooled air passage 114 through which the cooled air passing through the evaporator 103 is directly led to a ventilation duct 116.
Accordingly, when a fresh ventilation door 122 for opening and closing the cooled air passage 114 is opened, a cooled air is blown into the vehicle cabin from ventilation openings 121a and 121b which faces the vehicle cabin. Accordingly, in this case, it is possible to direct the cooled air against only the face of a driver for an adequate time, which makes the driver feel comfortable.
Apart from the above, automotive air conditioning devices belong to a device which is usually installed in a limited space, such as interior of an instrument panel. Thus, bulky structure of the device makes installation in a motor vehicle, particularly in a smaller motor vehicle difficult. Accordingly, for the need of reducing the device mounting space in the vehicle, various attempts have been made for reducing the size of the device.
However, in automotive air conditioning devices having the above-mentioned conventional fresh ventilation mode, a separate cooled air passage connecting to the ventilation duct must be provided to the conventional automotive air conditioning device. That is, in the devices, it is necessary to prepare a structure by which the passage is defined as well as separate parts, which causes an increase in cost and a need for a certain space for mounting therein the separate parts.
The present invention is provided for eliminating the above-mentioned drawbacks possessed by the conventional techniques. That is, a second object of the present invention is to provide an automotive air conditioning device which can possess a fresh ventilation mode irrespective of its simple, lower cost and compact construction.